1 files changed, 94 insertions, 15 deletions

diff --git a/fs/dquot.c b/fs/dquot.c
index 41b9dbd68b0e..dfba1623cccb 100644
--- a/fs/dquot.c
+++ b/fs/dquot.c
@@ -289,7 +289,15 @@ static void wait_on_dquot(struct dquot *dquot)
         mutex_unlock(&dquot->dq_lock);
 }
 
-#define mark_dquot_dirty(dquot) ((dquot)->dq_sb->dq_op->mark_dirty(dquot))
+static inline int dquot_dirty(struct dquot *dquot)
+{
+        return test_bit(DQ_MOD_B, &dquot->dq_flags);
+}
+
+static inline int mark_dquot_dirty(struct dquot *dquot)
+{
+        return dquot->dq_sb->dq_op->mark_dirty(dquot);
+}
 
 int dquot_mark_dquot_dirty(struct dquot *dquot)
 {
@@ -1441,31 +1449,43 @@ static inline void set_enable_flags(struct quota_info *dqopt, int type)
         switch (type) {
                 case USRQUOTA:
                         dqopt->flags |= DQUOT_USR_ENABLED;
+                        dqopt->flags &= ~DQUOT_USR_SUSPENDED;
                         break;
                 case GRPQUOTA:
                         dqopt->flags |= DQUOT_GRP_ENABLED;
+                        dqopt->flags &= ~DQUOT_GRP_SUSPENDED;
                         break;
         }
 }
 
-static inline void reset_enable_flags(struct quota_info *dqopt, int type)
+static inline void reset_enable_flags(struct quota_info *dqopt, int type,
+                                      int remount)
 {
         switch (type) {
                 case USRQUOTA:
                         dqopt->flags &= ~DQUOT_USR_ENABLED;
+                        if (remount)
+                                dqopt->flags |= DQUOT_USR_SUSPENDED;
+                        else
+                                dqopt->flags &= ~DQUOT_USR_SUSPENDED;
                         break;
                 case GRPQUOTA:
                         dqopt->flags &= ~DQUOT_GRP_ENABLED;
+                        if (remount)
+                                dqopt->flags |= DQUOT_GRP_SUSPENDED;
+                        else
+                                dqopt->flags &= ~DQUOT_GRP_SUSPENDED;
                         break;
         }
 }
 
+
 /*
  * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
  */
-int vfs_quota_off(struct super_block *sb, int type)
+int vfs_quota_off(struct super_block *sb, int type, int remount)
 {
-        int cnt;
+        int cnt, ret = 0;
         struct quota_info *dqopt = sb_dqopt(sb);
         struct inode *toputinode[MAXQUOTAS];
 
@@ -1475,9 +1495,17 @@ int vfs_quota_off(struct super_block *sb, int type)
                 toputinode[cnt] = NULL;
                 if (type != -1 && cnt != type)
                         continue;
+                /* If we keep inodes of quota files after remount and quotaoff
+                 * is called, drop kept inodes. */
+                if (!remount && sb_has_quota_suspended(sb, cnt)) {
+                        iput(dqopt->files[cnt]);
+                        dqopt->files[cnt] = NULL;
+                        reset_enable_flags(dqopt, cnt, 0);
+                        continue;
+                }
                 if (!sb_has_quota_enabled(sb, cnt))
                         continue;
-                reset_enable_flags(dqopt, cnt);
+                reset_enable_flags(dqopt, cnt, remount);
 
                 /* Note: these are blocking operations */
                 drop_dquot_ref(sb, cnt);
@@ -1493,7 +1521,8 @@ int vfs_quota_off(struct super_block *sb, int type)
                 put_quota_format(dqopt->info[cnt].dqi_format);
 
                 toputinode[cnt] = dqopt->files[cnt];
-                dqopt->files[cnt] = NULL;
+                if (!remount)
+                        dqopt->files[cnt] = NULL;
                 dqopt->info[cnt].dqi_flags = 0;
                 dqopt->info[cnt].dqi_igrace = 0;
                 dqopt->info[cnt].dqi_bgrace = 0;
@@ -1523,12 +1552,19 @@ int vfs_quota_off(struct super_block *sb, int type)
                                 mutex_unlock(&toputinode[cnt]->i_mutex);
                                 mark_inode_dirty(toputinode[cnt]);
                         }
-                        iput(toputinode[cnt]);
                         mutex_unlock(&dqopt->dqonoff_mutex);
+                        /* On remount RO, we keep the inode pointer so that we
+                         * can reenable quota on the subsequent remount RW.
+                         * But we have better not keep inode pointer when there
+                         * is pending delete on the quota file... */
+                        if (!remount)
+                                iput(toputinode[cnt]);
+                        else if (!toputinode[cnt]->i_nlink)
+                                ret = -EBUSY;
                 }
         if (sb->s_bdev)
                 invalidate_bdev(sb->s_bdev);
-        return 0;
+        return ret;
 }
 
 /*
@@ -1566,7 +1602,8 @@ static int vfs_quota_on_inode(struct inode *inode, int type, int format_id)
         invalidate_bdev(sb->s_bdev);
         mutex_lock(&inode->i_mutex);
         mutex_lock(&dqopt->dqonoff_mutex);
-        if (sb_has_quota_enabled(sb, type)) {
+        if (sb_has_quota_enabled(sb, type) ||
+                        sb_has_quota_suspended(sb, type)) {
                 error = -EBUSY;
                 goto out_lock;
         }
@@ -1589,6 +1626,7 @@ static int vfs_quota_on_inode(struct inode *inode, int type, int format_id)
 
         dqopt->ops[type] = fmt->qf_ops;
         dqopt->info[type].dqi_format = fmt;
+        dqopt->info[type].dqi_fmt_id = format_id;
         INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
         mutex_lock(&dqopt->dqio_mutex);
         if ((error = dqopt->ops[type]->read_file_info(sb, type)) < 0) {
@@ -1624,12 +1662,41 @@ out_fmt:
         return error; 
 }
 
+/* Reenable quotas on remount RW */
+static int vfs_quota_on_remount(struct super_block *sb, int type)
+{
+        struct quota_info *dqopt = sb_dqopt(sb);
+        struct inode *inode;
+        int ret;
+
+        mutex_lock(&dqopt->dqonoff_mutex);
+        if (!sb_has_quota_suspended(sb, type)) {
+                mutex_unlock(&dqopt->dqonoff_mutex);
+                return 0;
+        }
+        BUG_ON(sb_has_quota_enabled(sb, type));
+
+        inode = dqopt->files[type];
+        dqopt->files[type] = NULL;
+        reset_enable_flags(dqopt, type, 0);
+        mutex_unlock(&dqopt->dqonoff_mutex);
+
+        ret = vfs_quota_on_inode(inode, type, dqopt->info[type].dqi_fmt_id);
+        iput(inode);
+
+        return ret;
+}
+
 /* Actual function called from quotactl() */
-int vfs_quota_on(struct super_block *sb, int type, int format_id, char *path)
+int vfs_quota_on(struct super_block *sb, int type, int format_id, char *path,
+                 int remount)
 {
         struct nameidata nd;
         int error;
 
+        if (remount)
+                return vfs_quota_on_remount(sb, type);
+
         error = path_lookup(path, LOOKUP_FOLLOW, &nd);
         if (error < 0)
                 return error;
@@ -1709,10 +1776,19 @@ int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *d
 }
 
 /* Generic routine for setting common part of quota structure */
-static void do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
+static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
 {
         struct mem_dqblk *dm = &dquot->dq_dqb;
         int check_blim = 0, check_ilim = 0;
+        struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
+
+        if ((di->dqb_valid & QIF_BLIMITS &&
+             (di->dqb_bhardlimit > dqi->dqi_maxblimit ||
+              di->dqb_bsoftlimit > dqi->dqi_maxblimit)) ||
+            (di->dqb_valid & QIF_ILIMITS &&
+             (di->dqb_ihardlimit > dqi->dqi_maxilimit ||
+              di->dqb_isoftlimit > dqi->dqi_maxilimit)))
+                return -ERANGE;
 
         spin_lock(&dq_data_lock);
         if (di->dqb_valid & QIF_SPACE) {
@@ -1744,7 +1820,7 @@ static void do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
                         clear_bit(DQ_BLKS_B, &dquot->dq_flags);
                 }
                 else if (!(di->dqb_valid & QIF_BTIME))  /* Set grace only if user hasn't provided his own... */
-                        dm->dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace;
+                        dm->dqb_btime = get_seconds() + dqi->dqi_bgrace;
         }
         if (check_ilim) {
                 if (!dm->dqb_isoftlimit || dm->dqb_curinodes < dm->dqb_isoftlimit) {
@@ -1752,7 +1828,7 @@ static void do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
                         clear_bit(DQ_INODES_B, &dquot->dq_flags);
                 }
                 else if (!(di->dqb_valid & QIF_ITIME))  /* Set grace only if user hasn't provided his own... */
-                        dm->dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
+                        dm->dqb_itime = get_seconds() + dqi->dqi_igrace;
         }
         if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || dm->dqb_isoftlimit)
                 clear_bit(DQ_FAKE_B, &dquot->dq_flags);
@@ -1760,21 +1836,24 @@ static void do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
                 set_bit(DQ_FAKE_B, &dquot->dq_flags);
         spin_unlock(&dq_data_lock);
         mark_dquot_dirty(dquot);
+
+        return 0;
 }
 
 int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di)
 {
         struct dquot *dquot;
+        int rc;
 
         mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
         if (!(dquot = dqget(sb, id, type))) {
                 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
                 return -ESRCH;
         }
-        do_set_dqblk(dquot, di);
+        rc = do_set_dqblk(dquot, di);
         dqput(dquot);
         mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
-        return 0;
+        return rc;
 }
 
 /* Generic routine for getting common part of quota file information */